Control means for regulating the output of atomizers and the like



June 7, 1927. 1,631,475

' F. B. COMINS CONTROL MEANS FOR REGULATING THE OUTPUT OF ATOMIZERS ANDTHE LIKE J (if? 62 22390 Patented June 7, 1927.

onirsn STATES ara-s E'ATENT o new{ FRANK B, ooivrms, or NEwroiAssAoHUsET'rs, AssIeNoR T0 AMnRIoAN MoIs'rEN 11m ooMP NY, or BOSTON,MASSACHUSETTS, A CORPORATION o vr In I i 'coNrRoL MEANS FOR REGULATINGTHEOUTPUT oF AToMIznns'IANn H LIKE.

Application filedMarch 6,1924. serial No. 697,365.

g This invention relates to improvements in control means for regulatingthe. output of an atomizer and the like. More especially it provides an.improved rotary worm pump adapted, while running at uniform speed, tolift water from a well in varying quantities, dependent-upon'andcontrollable by varying the level at which the supply in the well ismaintained. The capacity of devices of this sort heretofore proposed,has been a substantially fixed rate Y for any given speed of pumprotation, ex-

cept in so far as the capacity may be I changed by stopping the pump andresetting a valve thereon which governs the admission of water to thelifting means. Accordingly, in the application of these devices tohumidifying apparatus, where the rate at which water is introduced intothe atmosphere is of paramount consideration, the worm pumps heretoforeknown have not been characterized by that regulatability of outputdesirable in apparatus of this sort, with possibility of control whilethe apparatus as a whole is in operation.

It is among the objects of the present invention to provide apparatuswhich has a regulatable lifting output, adapted to be controlledentirely by changing the level of the supply from which it pumps. Itfollows from this, that by devices already known, the rate of a systemof humidifiers, located at intervals throughout a considerable area, canbe controlled from a single place, without the necessity of visitingeach to regulate it, or of operating them at an excess rate withintermittent periods on cessation of humidifying action while the excessbecomes absorbed. Another object is to provide a pump of the characterdescribed that will be self cleaning and thereby free of any danger ofbecoming clogged while in use.

' These objects are attained by providing a controllable level of supplywater and a worm pump of helical for1n,'wh'0se radius increases as itsconvolutions progress upward, from the inlet or lower end of the pump,in the direction ofdelivery. Surrounding the worm is asleeve whichpreferably is more or less conical and which turns with the worm,preventing water from being throwniout laterally therefrom by ticularapplication of the invention illustrated, the water is delivered by thepump 1 and conveyor to the under side of the horizontal rotor of ahumidifier. The sleeve 'is belled outward at its upper end, toward atthe adjusted level, which signifies, in

each case, at a certain levelin the space within the well and outside ofthe sleeve which is immersed therein, when the apparatus is notoperating. By varying the level 'of the water the effect isgained of avarying depth of immersion of the sleeve in the water; and by this meansthe amount of water fed by the pump to the rotor is readily controlled.Assuming thatthe entrance opening for water in the bottom closure of thesleeve is at the level of the surface of the water'in: the well, or an"infinitesimal amount below it, the rotationfof the pump wilt lift thewater which enters through that opening but will ceasetaking water assoon as the well level has'fallen to below the opening so'that the waterseal thereof is broken; and the taking of water will begin again as soonas enough more water has been supplied'to raise the level. In practicethis would probably happen very quickly through the supply pipe, but asthe difference of level between this slightlyv lowered surface of waterin the swell and the tank supply level is only infinitesimal, the rateof flow would be relatively slow; and at any rate the quantity of waterflowing through the opening into thew or'm sent the minimum capacity atwhich the would always be small and -WOL1ld-repre- I pump can beoperated, it being assumed 7 that the pump is being "rotated at a highspeed .by' a motor on its shaft. However, if the level of water in thewellbe main ta'ined'at' a head of one inch, for example,fabovextheopening, equivalent to immersion centrifugal force, and servesas a part of the conveyor for the water. In: the par-j of the sleeve to"thatdepth,;thei*e will be I but the replacing such water as passesthrough the opening into the well. Assuming that the said opening has asize restrictive, so that the cross section is less than that of theworm, the amount of water which flows in through the opening under thishead of one inch "will be greater than where the head is zero as aboveassumed; and it will be less than if the head were two inches, which maybe taken as another variant level, for example. Thus by varying thelevel of water in the well the operative head'pressing water through therestricted orifice in the bottom of the sleeve is varied at will;

and thus the output from the pump to the rotor is controlled Meanwhile,owing to the conical nature of the construction, any

lint, and especially any matted, masses of lint which may have gatheredin the well and gotten into the worm, is carried forthrough the :pump.In practice it isobserved that although the water level may be one ortwo inches above the bottom entrance orifice of the sleeve when theapparatus is not rotating, the level inthe well tends to sink to thelevel of this bottom opening when the apparatus is working; principleabove stated applies equally, with the head being furnished through thesupply piping from the distant level-controlling supply tank.

It is intended that thepatent shall cover, by suitable expression in theappended claim, whatever features of patentable novelty exist in thecapacity control features of the invention.

tion; with the level control means being shown somewhat diagrammaticallyon reduced scale Figure 2 is a similar elevation of a modi- --fiedform-of sleeve; and

Figure 34s an elevation showing the de- -t11lS- of the water levelcontrol means.

Referring to the drawings, 10 designates a-rotorof a verticalhumidifier, fast on a shaft 12 having connection with some form of powersource (not shown) for effecting its rotation; and 14 is the bottom orpan of the humidifier, whose central portion Water is supplied to thewell through a pipe 17 threading into its bottom opening 18 and leadingfrom any controllable source, preferably a tank 19, having a ball float20,

placed at about the same level as the well.

By means hereinafter described, the controlling position of this floatcan be varied they extend farther from the shafts axis as the threadsprogress upward toward the rotor. A sleeve, 25, more or lesscomcal, 1s

fitted around these edges and at the top 25 is belled outward toward therotor. At the bottom of this sleeve is an opening 26 to permit water tobe fed to the worm pump, according to the head maintained above thelevel of the opening, by the float tank appartus 19 or other meansemployed for this purpose. This opening is sufficiently large to passenough water to supply the maximum delivery when the maximum head forwhich the apparatus issuited is employed, and yet isso small that thedegree of head will make a difference in the amount of flow through it.The sectional area of the spaces a between the threads being larger thanthis opening, and being of gradually increasing size, due to the coneshape, any foreign matter. passing through the opening will haveamplefreedom in the larger spaces between the threadsto pass out of the pumpwith the water. An annular baiiie 28 may be fixed between the well and-.the sleeve, to prevent any water which drains along the pan fromstriking the sides of the sleeve at a height from which it might becarried upward on the outside of'the sleeve and thence be discharged tothe rotor.

In Figure 2 a modified form ofsleeve is shown which is partly conicaland partly cylindricalv The cylindrical portion 25 extends from thebottom upward to about the maximum heightito which the water level risesin the well, and the conical portionw25 is from the upper end of thecylindrical portion to the belled top 25'. This form of sleeve has beenfound advantageous where the rotative speed is such that if the coneextended below water level some of the water surrounding it would beCarried up on the outside surface thereof and be discharged onto therotor. The vertical wallof the cylindrical portion does not so lift thewater about-it, and consequently the only water delivered-to the rotoris that which passes through the interior of the sleeve. :If an annularspace exists, as illustrated, between the edge of the worms convolutionsand the inner wall of the cylindrical portion, that does not appreciablyeffect the work of the pump, for even though it does permit of a fallingback over the edge of some of the water lifted, thisloss is incidentallycompensated for by the-slight raising of the level of the supply, abovethat at which it lUO . would otherwise stand when the operator sets thelevel of supply tank at whatever point gives the desired humidifieroutput.

is lifted along the incline of the worm, and V gradually begins torotate and be thrown outward laterally against the inner surface of thesleeve by centrifugal force. When it reaches the upper end of the worm,the water continues upward on the inner wallof the sleeve and finally,at its termination, leaps across the small space between" the edge ofthe latter and the rotor, after which it continues on the rotor, underthe influence of centrifugal force, to the fog, generating means of thehumidifier. When the supply level is low only a small quantity reachesthe thread surface, but if the supply level is raised a greater amountis lifted. In consequence, the output of the pump at any instant isdependent upon the height of the water in the well or supply, so that bycontrolling the latter the output of the pump is regulated. By keepingthe supply level constant and the rotative speed unchanged, the

amount ofwater delivered to the rotor will remain the same. Withoutstoppingoraltering the pump speed, and without visiting the severalhumidifiers the pump delivery of each may be varied, by merely alteringthe level of the supply to change the effective head above the sleeveopening 26.. Thus the capacity of the pump may be varied while thehumidifier continues in operation.

In Figure 3 is shown a dev1ce for controlling the supply level,comprising a' plunger valve 22, subjected constantly to supply pressuretending to open it, and a float adjuster 21 pivotally mounted on thevalve at 21 having suitable; connection with the plunger so that -whenswung upward about its pivot the plunger is seated and the valve closed.The stem 20 of the float 20 is movable within a hollow in the under sideof the adjuster about a pivot screw 31. Its limit of swing upward, withrespect to the adjuster, isdetermined by the setting of the screw 30whichthreads through the ad juster and bottoms on the stem. According lyif this screw is turned inward, the float is thereby set downward sothat when raised by the water in thetank it will engage the valveop'eratively, to close it, at a lower level of water than it would ifthe screw had been set higher. In consequence the supply is maintained.at any desired level according to the setting of screw 30.

, Another method of control is found in the valve 31 set in the lineofsupply. If this be partly closed, so as to restrict to-a desireddegree the flow of water to the humidifier, the supply to itmaybelregulated to any-. thing less than the maximum which the level intank 19 would provide, thus getting an effect of lowered headon theopening 26.

in the bottom of the pump sleeve, so long as the pump is operating andconstantly removing waterrfrom the well. The differ-' 1 ential, betweenthe draft of water from the well by the pump, and'the supply to the;well by return drainage from th'epan 14k and fresh supply through thevalve 81,

under head of the level in tank 19,- then constitutes the factor whichdetermines the amount that will fiow'in through the opening 26 to belifted. Where the supply comes through a reducing or flow restrictingvalve,

as 31, it may be more accurate to speak of this differential as avirtual head of liquid pressure at the inlet opening 26, but it will beunderstood that in either case reference is made to the variations ofpressure with which the water is' opening. 7 r

- I claim as my invention:

to the rotor of a humidifier or the like, comprising a rotatable shafthaving a helical worm thread and a housing therefor, having an openingbelow the level of the sup ply, for admission of liquid to thespacebetween the convolutions; said opening being of such small area andso arranged that under the working head it does not admit as much wateras the worm can lift, so that a variation of head 'ofthe water to whichit is exposed makes material variation in pressed into the inlet i theamount of water that flows through the day of February, 1924.

FRANK B. .COMINS.

Means for lifting liquid from asupply .7

